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<html lang="en">

<head>
    <meta charset="UTF-8">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <title>Document</title>
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<body>
    <script>
        /* 字面量：
        1 2 3 4 5
        */
        // alert(111111111)

        //变量：
        // 先声明声名
        var a;
        // 赋值
        a = 111;
        a = 123;
        var b = 333;
        c = 9;
        console.log(a, b, c);
    </script>
</body>

</html>